The sockets are enabled for connection of USB storage devices and also USB network devices using a specific chipset (Ralink 3070).

It might well be possible to use them as a small power source for example with a IR receiver, Your mention of dongle is not specific – If you are thinking of it providing, for example, network connectivity, then it must have the correct chipset, plenty of posts here giving the chipset and Humax sell one themselves. There have been recent changes that have resulted in some brands no longer working the EDIMAX (with the correct chipset) is one that continues to work.

Wikipedia: “A dongle is a small piece of hardware that attaches to a computer, TV, or other electronic device in order to enable additional functions such as copy protection, audio, video, games, data, or other services. These services are available only when the dongle is attached.”

iantresman – 5 minutes ago  » 

Thanks for that. Yes, it is just a bluetooth transmitter.

Are you wanting to transmit the box audio by bluetooth to say a external speaker ?